Decreases Energy Cost of ____ Spells by 5. (20% Chance)

I was thinking about a mod like this for rods/staves/focii. Any thoughts?

Would be nice, but can be a little unbalanced, seeing that spamming spells can go on 20% longer.

Well, mathematically, that 20% chance would allow you to spam for 20% longer on 5 energy skills...I think...

Mathematics -_- never did well.

Perhaps minimum spell cost would be 5?
Make it work for spell with energy costs of 10 or higher.

So if I cast a 10 energy spell 10 times, 2 out of those 10 times the energy cost would be reduced by 5 energy.

Balanced? Yes? No?
Discuss?

erm...hmmm... yeah i suppose

/signed

very unbalanced, here's why, think of this senerio:

You're playing as a monk. You got 4 energy left due to some e-denial mesmer and you don't have any energy regen left. You switch to your -5 energy cost want/staff. And just keep smashing the button on it until it worked on that 20% chance.

see why? E-denial becomes useless and you can always get that one spell out by keep trying it.

What if, this would only apply to spells with at least 10 energy cost or higher?
Would it still be unbalanced?

Or perhaps getting 5 energy after casting (20% Chance)

Hm... sounds good

And yes, to balance it out it would only apply to spells costing 10 energy or more, and if you have 8 energy and hammer the button it doesn't work because you don't have 10 energy, as the spell requires, only when you get the required amount of energy the spell works, even if it does get the -5 energy cost thingy, see what I mean?

You cant cast spells at all if you have no energy. The way this would work, is that your spell would cost 5 less energy when you cast it (which means you still need 5 energy to cast it, even though there would be a 20% change you wont lose it). The instantaneous calculation could be done so that the energy requirement is done first, following this mod percentge immediately after.

Increasing the cost to 10 would make the description of the mod too long, and rather undesireable.